UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED

MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number   811-02737

Fidelity Summer Street Trust

 (Exact name of registrant as specified in charter)

245 Summer St., Boston, MA 02210

 (Address of principal executive offices)       (Zip code)

Nicole Macarchuk, Secretary

245 Summer St.

Boston, Massachusetts  02210

(Name and address of agent for service)

Registrant's telephone number, including area code:

617-563-7000

Date of fiscal year end:	July 31
Date of reporting period:	January 31, 2025

Item 1.

Reports to Stockholders

SEMI-ANNUAL SHAREHOLDER REPORT | AS OF JANUARY 31, 2025

Fidelity® SAI Real Estate Fund

Fidelity® SAI Real Estate Fund :  FSRJX 

This semi-annual shareholder report contains information about Fidelity® SAI Real Estate Fund for the period September 4, 2024 to January 31, 2025. You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.

What were your Fund costs for the last six months?

(based on hypothetical $10,000 investment)

 

	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Fidelity® SAI Real Estate Fund A	$ 24	0.59%

A Expenses for the full reporting period would be higher.

 

Key Fund Statistics

(as of January 31, 2025)

KEY FACTS
Fund Size	$1,206,276,523
Number of Holdings	43
Portfolio TurnoverA	8%

A Amount not annualized

What did the Fund invest in?
(as of January 31, 2025)

TOP INDUSTRIES (% of Fund's net assets)
Specialized REITs	30.9
Residential REITs	17.3
Industrial REITs	16.2
Retail REITs	15.6
Health Care REITs	10.6
Real Estate Management & Development	8.0
Hotel & Resort REITs	0.5

ASSET ALLOCATION (% of Fund's net assets)

Common Stocks - 99.1                    

Short-Term Investments and Net Other Assets (Liabilities) - 0.9

GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)

United States - 100.0                   

TOP HOLDINGS (% of Fund's net assets)
Prologis Inc	10.8
American Tower Corp	9.3
Equinix Inc	8.2
Welltower Inc	6.1
CBRE Group Inc Class A	4.8
Kimco Realty Corp	4.6
Ventas Inc	4.5
UDR Inc	4.0
Public Storage Operating Co	3.9
NNN REIT Inc	3.7
	59.9

Fidelity, the Fidelity Investments Logo and all other Fidelity trademarks or service marks used herein are trademarks or service marks of FMR LLC. Any third-party marks that are used herein are trademarks or service marks of their respective owners. © 2025 FMR LLC. All rights reserved.
		For additional information about the Fund; including its prospectus, financial information, holdings and proxy information, scan the QR code or visit fundresearch.fidelity.com/prospectus/sec 1.9918119.100    7630-TSRS-0425

Item 2.

Code of Ethics

Not applicable.

Item 3.

Audit Committee Financial Expert

Not applicable.

Item 4.

Principal Accountant Fees and Services

Not applicable.

Item 5.

Audit Committee of Listed Registrants

Not applicable.

Item 6.  

Investments

(a)

Not applicable.

(b)

Not applicable

Item 7.

Financial Statements and Financial Highlights for Open-End Management Investment Companies

Fidelity® SAI Real Estate Fund

Semi-Annual Report

January 31, 2025

Offered exclusively to certain clients of the Adviser, or its affiliates, including Strategic Advisers LLC (Strategic Advisers) - not available for sale to the general public. Fidelity® SAI is a product name of Fidelity® funds dedicated to certain programs affiliated with Strategic Advisers.

Contents

To view a fund's proxy voting guidelines and proxy voting record for the 12-month period ended June 30, visit http://www.fidelity.com/proxyvotingresults or visit the Securities and Exchange Commission's (SEC) web site at http://www.sec.gov.

You may also call 1-800-544-3455 to request a free copy of the proxy voting guidelines.

Standard & Poor's, S&P and S&P 500 are registered service marks of The McGraw-Hill Companies, Inc. and have been licensed for use by Fidelity Distributors Corporation.

Other third-party marks appearing herein are the property of their respective owners.

All other marks appearing herein are registered or unregistered trademarks or service marks of FMR LLC or an affiliated company. © 2025 FMR LLC. All rights reserved.

This report and the financial statements contained herein are submitted for the general information of the shareholders of the Fund. This report is not authorized for distribution to prospective investors in the Fund unless preceded or accompanied by an effective prospectus.

A fund files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-PORT. Forms N-PORT are available on the SEC's web site at http://www.sec.gov. A fund's Forms N-PORT may be reviewed and copied at the SEC's Public Reference Room in Washington, DC. Information regarding the operation of the SEC's Public Reference Room may be obtained by calling 1-800-SEC-0330.

For a complete list of a fund's portfolio holdings, view the most recent holdings listing, semiannual report, or annual report on Fidelity's web site at http://www.fidelity.com, http://www.institutional.fidelity.com, or http://www.401k.com, as applicable.

NOT FDIC INSURED •MAY LOSE VALUE •NO BANK GUARANTEE

Neither the Fund nor Fidelity Distributors Corporation is a bank.

Item 7: Financial Statements and Financial Highlights for Open-End Management Investment Companies (Semi-Annual Report)

Fidelity® SAI Real Estate Fund

Schedule of Investments January 31, 2025 (Unaudited)

Showing Percentage of Net Assets

Common Stocks - 99.1%
	Shares	Value ($)
UNITED STATES - 99.1%
Real Estate - 99.1%
Health Care REITs - 10.6%
Ventas Inc	896,214	54,149,250
Welltower Inc	537,218	73,319,513
		127,468,763
Hotel & Resort REITs - 0.5%
Ryman Hospitality Properties Inc	55,911	5,861,708
Industrial REITs - 16.2%
Americold Realty Trust Inc	1,253,414	27,387,096
Prologis Inc	1,096,607	130,770,385
STAG Industrial Inc Class A	666,694	22,787,601
Terreno Realty Corp	229,357	15,004,535
		195,949,617
Real Estate Management & Development - 8.0%
CBRE Group Inc Class A (a)	400,383	57,951,435
Compass Inc Class A (a)	1,558,245	11,297,276
CoStar Group Inc (a)	249,316	19,097,606
Jones Lang LaSalle Inc (a)	29,700	8,399,160
		96,745,477
Residential REITs - 17.3%
American Homes 4 Rent Class A	776,382	26,886,109
Camden Property Trust	131,349	14,935,695
Elme Communities	400,301	6,108,593
Equity LifeStyle Properties Inc	58,467	3,826,664
Equity Residential	532,766	37,629,263
Invitation Homes Inc	642,705	20,020,261
Mid-America Apartment Communities Inc	101,356	15,464,898
Sun Communities Inc	287,921	36,422,007
UDR Inc	1,129,444	47,142,993
		208,436,483
Retail REITs - 15.6%
Acadia Realty Trust	195,770	4,510,541
Curbline Properties Corp	370,778	9,072,938
FrontView REIT Inc	198,500	3,422,140
InvenTrust Properties Corp	125,900	3,744,266
Kimco Realty Corp	2,463,561	55,306,945
Macerich Co/The	582,300	12,100,194
NNN REIT Inc	1,142,021	44,984,207
Phillips Edison & Co Inc	279,692	10,161,210
Regency Centers Corp	180,025	12,932,996
SITE Centers Corp	261,689	3,920,101
Tanger Inc	257,289	8,444,225
Urban Edge Properties	946,279	19,247,315
		187,847,078
Specialized REITs - 30.9%
American Tower Corp	606,210	112,118,540
CubeSmart	485,076	20,227,669
Digital Realty Trust Inc	254,455	41,694,996
Equinix Inc	108,597	99,220,735
Extra Space Storage Inc	45,345	6,983,130
Four Corners Property Trust Inc	420,201	11,526,113
Iron Mountain Inc	17,800	1,807,946
Lamar Advertising Co Class A	142,385	18,000,312
Public Storage Operating Co	159,135	47,498,615
SBA Communications Corp Class A	70,248	13,878,195
		372,956,251
TOTAL REAL ESTATE		1,195,265,377
TOTAL COMMON STOCKS  (Cost $1,264,898,046)		1,195,265,377

Money Market Funds - 0.8%
	Yield (%)	Shares	Value ($)
Fidelity Cash Central Fund (b)  (Cost $10,174,590)	4.37	10,172,556	10,174,590

TOTAL INVESTMENT IN SECURITIES - 99.9%  (Cost $1,275,072,636)	1,205,439,967
NET OTHER ASSETS (LIABILITIES) - 0.1%	836,556
NET ASSETS - 100.0%	1,206,276,523

Legend

(a) Non-income producing  

(b) Affiliated fund that is generally available only to investment companies and other accounts managed by Fidelity Investments. The rate quoted is the annualized seven-day yield of the fund at period end. A complete unaudited listing of the fund's holdings as of its most recent quarter end is available upon request. In addition, each Fidelity Central Fund's financial statements are available on the SEC's website or upon request.  

Affiliated Central Funds

Fiscal year to date information regarding the Fund's investments in Fidelity Central Funds, including the ownership percentage, is presented below.

Affiliate	Value, beginning of period ($)	Purchases ($)	Sales Proceeds ($)	Dividend Income ($)	Realized Gain (loss) ($)	Change in Unrealized appreciation (depreciation) ($)	Value, end of period ($)	Shares, end of period	% ownership, end of period
Fidelity Cash Central Fund	-	219,088,065	208,913,475	288,704	-	-	10,174,590	10,172,556	0.0%
Total	-	219,088,065	208,913,475	288,704	-	-	10,174,590	10,172,556

Amounts in the dividend income column in the above table include any capital gain distributions from underlying funds, which are presented in the corresponding line item in the Statement of Operations, if applicable.

Amounts included in the purchases and sales proceeds columns may include in-kind transactions, if applicable.
 

Investment Valuation

The following is a summary of the inputs used, as of January 31, 2025, involving the Fund's assets and liabilities carried at fair value. The inputs or methodology used for valuing securities may not be an indication of the risk associated with investing in those securities. For more information on valuation inputs, and their aggregation into the levels used below, please refer to the Investment Valuation section in the accompanying Notes to Financial Statements.

Valuation Inputs at Reporting Date:
Description	Total ($)	Level 1 ($)	Level 2 ($)	Level 3 ($)
Investments in Securities:
Common Stocks
Real Estate	1,195,265,377	1,195,265,377	-	-
Money Market Funds	10,174,590	10,174,590	-	-
Total Investments in Securities:	1,205,439,967	1,205,439,967	-	-

Financial Statements (Unaudited)

Statement of Assets and Liabilities
As of January 31, 2025 (Unaudited)
Assets
Investment in securities, at value  - See accompanying schedule:
Unaffiliated issuers (cost $1,264,898,046)	$	1,195,265,377
Fidelity Central Funds (cost $10,174,590)		10,174,590
Total Investment in Securities (cost $1,275,072,636)			$	1,205,439,967
Receivable for investments sold				813,305
Receivable for fund shares sold				2,186,946
Dividends receivable				1,773,549
Distributions receivable from Fidelity Central Funds				28,766
Prepaid expenses				17,003
Other receivables				75,025
Total assets				1,210,334,561
Liabilities
Payable for investments purchased	$	2,675,825
Payable for fund shares redeemed		603,923
Accrued management fee		551,235
Registration fee payable		195,119
Other payables and accrued expenses		31,936
Total liabilities				4,058,038
Net Assets			$	1,206,276,523
Net Assets consist of:
Paid in capital			$	1,280,717,624
Total accumulated earnings (loss)				(74,441,101)
Net Assets			$	1,206,276,523
Net Asset Value, offering price and redemption price per share ($1,206,276,523 ÷ 126,386,115 shares)			$	9.54

Statement of Operations
For the period September 4, 2024 (commencement of operations) through January 31, 2025 (Unaudited)
Investment Income
Dividends			$	12,600,026
Income from Fidelity Central Funds				288,704
Total income				12,888,730
Expenses
Management fee	$	2,070,841
Custodian fees and expenses		11,090
Independent trustees' fees and expenses		1,113
Registration fees		551,928
Audit fees		21,882
Legal		80
Miscellaneous		206
Total expenses before reductions		2,657,140
Expense reductions		(183,274)
Total expenses after reductions				2,473,866
Net Investment income (loss)				10,414,864
Realized and Unrealized Gain (Loss)
Net realized gain (loss) on:
Investment Securities:
Unaffiliated issuers		(3,573,091)
Foreign currency transactions		10,296
Total net realized gain (loss)				(3,562,795)
Change in net unrealized appreciation (depreciation) on investment securities				(69,632,669)
Net gain (loss)				(73,195,464)
Net increase (decrease) in net assets resulting from operations			$	(62,780,600)

Statement of Changes in Net Assets
		For the period September 4, 2024 (commencement of operations) through January 31, 2025 (Unaudited)
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$	10,414,864
Net realized gain (loss)		(3,562,795)
Change in net unrealized appreciation (depreciation)		(69,632,669)
Net increase (decrease) in net assets resulting from operations		(62,780,600)
Distributions to shareholders		(11,660,501)
Share transactions
Proceeds from sales of shares		1,327,364,376
Reinvestment of distributions		5,166,431
Cost of shares redeemed		(51,813,183)
Net increase (decrease) in net assets resulting from share transactions		1,280,717,624
Total increase (decrease) in net assets		1,206,276,523
Net Assets
Beginning of period		-
End of period	$	1,206,276,523
Other Information
Shares
Sold		131,136,273
Issued in reinvestment of distributions		529,775
Redeemed		(5,279,933)
Net increase (decrease)		126,386,115

Financial Highlights

 

Fidelity® SAI Real Estate Fund

		Six months ended (Unaudited) January 31, 2025 A
Selected Per-Share Data
Net asset value, beginning of period	$	10.00
Income from Investment Operations
Net investment income (loss) B,C		.10
Net realized and unrealized gain (loss)		(.46)
Total from investment operations		(.36)
Distributions from net investment income		(.09)
Distributions from net realized gain		(.01)
Total distributions		(.10)
Net asset value, end of period	$	9.54
Total Return D,E		(3.62) %
Ratios to Average Net Assets C,F,G
Expenses before reductions		.64% H
Expenses net of fee waivers, if any		.59 % H
Expenses net of all reductions		.59% H
Net investment income (loss)		2.50% H
Supplemental Data
Net assets, end of period (000 omitted)	$	1,206,277
Portfolio turnover rate I		8 % J

AFor the period September 4, 2024 (commencement of operations) through January 31, 2025.

BCalculated based on average shares outstanding during the period.

CNet investment income (loss) is affected by the timing of the declaration of dividends by any underlying mutual funds or exchange-traded funds (ETFs). Net investment income (loss) of any mutual funds or ETFs is not included in the Fund's net investment income (loss) ratio.

DTotal returns for periods of less than one year are not annualized.

ETotal returns would have been lower if certain expenses had not been reduced during the applicable periods shown.

FFees and expenses of any underlying mutual funds or exchange-traded funds (ETFs) are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of these expenses. For additional expense information related to investments in Fidelity Central Funds, please refer to the "Investments in Fidelity Central Funds" note found in the Notes to Financial Statements section of the most recent Annual or Semi-Annual report.

GExpense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed, waived, or reduced through arrangements with the investment adviser, brokerage services, or other offset arrangements, if applicable, and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur.

HAnnualized.

IAmount does not include the portfolio activity of any underlying mutual funds or exchange-traded funds (ETFs), derivatives or securities that mature within one year from acquisition.

JAmount not annualized.

Notes to Financial Statements

 (Unaudited)

For the period ended January 31, 2025

1. Organization.

Fidelity SAI Real Estate Fund (the Fund) is a non-diversified fund of Fidelity Summer Street Trust (the Trust) and is authorized to issue an unlimited number of shares. Shares are offered exclusively to certain clients of Fidelity Management & Research Company LLC (FMR) or its affiliates. The Trust is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Massachusetts business trust.

2. Investments in Fidelity Central Funds.

Funds may invest in Fidelity Central Funds, which are open-end investment companies generally available only to other investment companies and accounts managed by the investment adviser and its affiliates. The Schedule of Investments lists any Fidelity Central Funds held as an investment as of period end, but does not include the underlying holdings of each Fidelity Central Fund. An investing fund indirectly bears its proportionate share of the expenses of the underlying Fidelity Central Funds.

Based on its investment objective, each Fidelity Central Fund may invest or participate in various investment vehicles or strategies that are similar to those of the investing fund. These strategies are consistent with the investment objectives of the investing fund and may involve certain economic risks which may cause a decline in value of each of the Fidelity Central Funds and thus a decline in the value of the investing fund.

 

Fidelity Central Fund	Investment Manager	Investment Objective	Investment Practices	Expense RatioA
Fidelity Money Market Central Funds	Fidelity Management & Research Company LLC (FMR)	Each fund seeks to obtain a high level of current income consistent with the preservation of capital and liquidity.	Short-term Investments	Less than .005%

A Expenses expressed as a percentage of average net assets and are as of each underlying Central Fund's most recent annual or semi-annual shareholder report.

A complete unaudited list of holdings for each Fidelity Central Fund is available upon request or at the Securities and Exchange Commission website at www.sec.gov. In addition, the financial statements of the Fidelity Central Funds which contain the significant accounting policies (including investment valuation policies) of those funds, and are not covered by the Report of Independent Registered Public Accounting Firm, are available on the Securities and Exchange Commission website or upon request.

3. Significant Accounting Policies.

The Fund is an investment company and applies the accounting and reporting guidance of the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946 Financial Services - Investment Companies. The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP), which require management to make certain estimates and assumptions at the date of the financial statements. Actual results could differ from those estimates. The Fund operates as a single operating segment. The Fund's income, expenses, assets, and performance are regularly monitored and assessed as a whole by the investment adviser and other individuals responsible for oversight functions of the Trust, using the information presented in the financial statements and financial highlights. Subsequent events, if any, through the date that the financial statements were issued have been evaluated in the preparation of the financial statements. The Fund's Schedule of Investments lists any underlying mutual funds or exchange-traded funds (ETFs) but does not include the underlying holdings of these funds. The following summarizes the significant accounting policies of the Fund:

Investment Valuation. Investments are valued as of 4:00 p.m. Eastern time on the last calendar day of the period. The Board of Trustees (the Board) has designated the Fund's investment adviser as the valuation designee responsible for the fair valuation function and performing fair value determinations as needed. The investment adviser has established a Fair Value Committee (the Committee) to carry out the day-to-day fair valuation responsibilities and has adopted policies and procedures to govern the fair valuation process and the activities of the Committee. In accordance with these fair valuation policies and procedures, which have been approved by the Board, the Fund attempts to obtain prices from one or more third party pricing services or brokers to value its investments. When current market prices, quotations or currency exchange rates are not readily available or reliable, investments will be fair valued in good faith by the Committee, in accordance with the policies and procedures. Factors used in determining fair value vary by investment type and may include market or investment specific events, transaction data, estimated cash flows, and market observations of comparable investments. The frequency that the fair valuation procedures are used cannot be predicted and they may be utilized to a significant extent. The Committee manages the Fund's fair valuation practices and maintains the fair valuation policies and procedures. The Fund's investment adviser reports to the Board information regarding the fair valuation process and related material matters. 

The Fund categorizes the inputs to valuation techniques used to value its investments into a disclosure hierarchy consisting of three levels as shown below:

Level 1 - unadjusted quoted prices in active markets for identical investments

Level 2 - other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, etc.)

Level 3 - unobservable inputs (including the Fund's own assumptions based on the best information available)

Valuation techniques used to value the Fund's investments by major category are as follows:

Equity securities, including restricted securities, for which market quotations are readily available, are valued at the last reported sale price or official closing price as reported by a third party pricing service on the primary market or exchange on which they are traded and are categorized as Level 1 in the hierarchy. In the event there were no sales during the day or closing prices are not available, securities are valued at the last quoted bid price or may be valued using the last available price and are generally categorized as Level 2 in the hierarchy. For foreign equity securities, when market or security specific events arise, comparisons to the valuation of American Depositary Receipts (ADRs), futures contracts, Exchange-Traded Funds (ETFs) and certain indexes as well as quoted prices for similar securities may be used and would be categorized as Level 2 in the hierarchy. For equity securities, including restricted securities, where observable inputs are limited, assumptions about market activity and risk are used and these securities may be categorized as Level 3 in the hierarchy.

Investments in open-end mutual funds ,including the Fidelity Central Funds, are valued at their closing net asset value (NAV) each business day and are categorized as Level 1 in the hierarchy.

Changes in valuation techniques may result in transfers in or out of an assigned level within the disclosure hierarchy. The aggregate value of investments by input level as of January 31, 2025 is included at the end of the Fund's Schedule of Investments.

Foreign Currency. Certain Funds may use foreign currency contracts to facilitate transactions in foreign-denominated securities. Gains and losses from these transactions may arise from changes in the value of the foreign currency or if the counterparties do not perform under the contracts' terms.

Foreign-denominated assets, including investment securities, and liabilities are translated into U.S. dollars at the exchange rates at period end. Purchases and sales of investment securities, income and dividends received, and expenses denominated in foreign currencies are translated into U.S. dollars at the exchange rate in effect on the transaction date.

The effects of exchange rate fluctuations on investments are included with the net realized and unrealized gain (loss) on investment securities. Other foreign currency transactions resulting in realized and unrealized gain (loss) are disclosed separately.

Investment Transactions and Income. For financial reporting purposes, the Fund's investment holdings and NAV include trades executed through the end of the last business day of the period. The NAV per share for processing shareholder transactions is calculated as of the close of business of the New York Stock Exchange (NYSE), normally 4:00 p.m. Eastern time and includes trades executed through the end of the prior business day. Gains and losses on securities sold are determined on the basis of identified cost. Commissions paid to certain brokers with whom the investment adviser, or its affiliates, places trades on behalf of a fund include an amount in addition to trade execution, which may be rebated back to a fund. Any such rebates are included in net realized gain (loss) on investments in the Statement of Operations. Dividend income is recorded on the ex-dividend date, except for certain dividends from foreign securities where the ex-dividend date may have passed, which are recorded as soon as the Fund is informed of the ex-dividend date. Non-cash dividends included in dividend income, if any, are recorded at the fair market value of the securities received. Income and capital gain distributions from Fidelity Central Funds, if any, are recorded on the ex-dividend date. Certain distributions received by the Fund represent a return of capital or capital gain. The Fund determines the components of these distributions subsequent to the ex-dividend date, based upon receipt of tax filings or other correspondence relating to the underlying investment. These distributions are recorded as a reduction of cost of investments and/or as a realized gain. Investment income is recorded net of foreign taxes withheld where recovery of such taxes is uncertain.

Expenses. Expenses directly attributable to a fund are charged to that fund. Expenses attributable to more than one fund are allocated among the respective funds on the basis of relative net assets or other appropriate methods. Expenses included in the accompanying financial statements reflect the expenses of that fund and do not include any expenses associated with any underlying mutual funds or exchange-traded funds. Although not included in a fund's expenses, a fund indirectly bears its proportionate share of these expenses through the net asset value of each underlying mutual fund or exchange-traded fund. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

Income Tax Information and Distributions to Shareholders. Each year, the Fund intends to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code, including distributing substantially all of its taxable income and realized gains. As a result, no provision for U.S. Federal income taxes is required. The Fund files a U.S. federal tax return, in addition to state and local tax returns as required. The Fund's federal income tax returns are subject to examination by the Internal Revenue Service (IRS) for a period of three fiscal years after they are filed. State and local tax returns may be subject to examination for an additional fiscal year depending on the jurisdiction. Foreign taxes are provided for based on the Fund's understanding of the tax rules and rates that exist in the foreign markets in which it invests.

Distributions are declared and recorded on the ex-dividend date. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP.

Capital accounts within the financial statements are adjusted for permanent book-tax differences. These adjustments have no impact on net assets or the results of operations. Capital accounts are not adjusted for temporary book-tax differences which will reverse in a subsequent period.

As of period end, the cost and unrealized appreciation (depreciation) in securities, and derivatives if applicable, for federal income tax purposes were as follows:

 

Gross unrealized appreciation	$28,300,363
Gross unrealized depreciation	(107,027,685)
Net unrealized appreciation (depreciation)	$(78,727,322)
Tax cost	$1,284,167,289

New Accounting Pronouncements. FASB Accounting Standards Update (ASU) 2023-07 Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures became effective in this reporting period. ASU 2023-07 enhances segment information disclosure in the notes to financial statements.

In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures. Effective for annual periods beginning after December 15, 2024, the amendments require greater disaggregation of disclosures related to income taxes paid. The ASU allows for early adoption and amendments should be applied on a prospective basis. Management is currently evaluating the impact of the ASU but does not expect this guidance to materially impact the financial statements.

4. Purchases and Sales of Investments.

Purchases and sales of securities, other than short-term securities and in-kind transactions, as applicable, are noted in the table below.

 

	Purchases ($)	Sales ($)
Fidelity SAI Real Estate Fund	1,371,269,410	93,136,776

5. Fees and Other Transactions with Affiliates.

Management Fee. Fidelity Management & Research Company LLC (the investment adviser) and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .498% of the Fund's average net assets.

Interfund Trades. Funds may purchase from or sell securities to other Fidelity Funds under procedures adopted by the Board. The procedures have been designed to ensure these interfund trades are executed in accordance with Rule 17a-7 of the 1940 Act. Any interfund trades are included within the respective purchases and sales amounts shown in the Purchases and Sales of Investments note. Interfund trades during the period are noted in the table below.

 

	Purchases ($)	Sales ($)	Realized Gain (Loss) ($)
Fidelity SAI Real Estate Fund	99,602,535	5,593,288	(441,648)

6. Expense Reductions.

The investment adviser contractually agreed to reimburse the Fund to the extent annual operating expenses exceeded .60% of average net assets. This reimbursement will remain in place through November 30, 2025. Some expenses, for example the compensation of the independent Trustees, and certain miscellaneous expenses such as proxy and shareholder meeting expenses, are excluded from this reimbursement. During the period this reimbursement reduced the Fund's expenses by $183,274.

7. Other.

A fund's organizational documents provide former and current trustees and officers with a limited indemnification against liabilities arising in connection with the performance of their duties to the fund. In the normal course of business, a fund may also enter into contracts that provide general indemnifications. A fund's maximum exposure under these arrangements is unknown as this would be dependent on future claims that may be made against a fund. The risk of material loss from such claims is considered remote.

8. Risk and Uncertainties.

Many factors affect a fund's performance. Developments that disrupt global economies and financial markets, such as pandemics, epidemics, outbreaks of infectious diseases, war, terrorism, and environmental disasters, may significantly affect a fund's investment performance. The effects of these developments to a fund will be impacted by the types of securities in which a fund invests, the financial condition, industry, economic sector, and geographic location of an issuer, and a fund's level of investment in the securities of that issuer. Significant concentrations in security types, issuers, industries, sectors, and geographic locations may magnify the factors that affect a fund's performance.

Item 8: Changes in and Disagreements with Accountants for Open-End Management Investment Companies

(Unaudited)

Note: This is not applicable for any fund included in this document.

Item 9: Proxy Disclosures for Open-End Management Investment Companies

(Unaudited)

Note: This is not applicable for any fund included in this document.

Item 10: Remuneration Paid to Directors, Officers, and others of Open-End Management Investment Companies

(Unaudited)

Note: This information is disclosed as part of the financial statements for each Fund as part of Item 7: Financial Statements and Financial Highlights for Open-End Management Investment companies.

Item 11: Statement Regarding Basis for Approval of Investment Advisory Contract

(Unaudited)

Board Approval of Investment Advisory Contracts and Management Fees

Fidelity SAI Real Estate Fund 

At its March 2024 meeting, the Board of Trustees, including the Independent Trustees (together, the Board), voted to approve the management contract with Fidelity Management & Research Company LLC (FMR) and the sub-advisory agreements with affiliates of FMR (together, the Advisory Contracts) for the fund. FMR and the sub-advisers are collectively referred to herein as the Investment Advisers. The Board, assisted by the advice of fund counsel and Independent Trustees' counsel, considered a broad range of information.

Nature, Extent, and Quality of Services Provided. The Board considered Fidelity's staffing as it relates to the fund, including the backgrounds of investment personnel of Fidelity, and also considered the fund's investment objective, strategies, and related investment philosophy. The Board considered the structure of the investment personnel compensation program and whether the structure provides appropriate incentives to act in the best interests of the fund.

Resources Dedicated to Investment Management and Support Services. The Board and the Fund Oversight and Research Committees reviewed the general qualifications and capabilities of Fidelity's investment staff, including its size, education, experience, and resources, as well as Fidelity's approach to recruiting, training, managing, and compensating investment personnel. The Board noted the resources devoted to Fidelity's global investment organization and that Fidelity's analysts have extensive resources, tools and capabilities that allow them to conduct sophisticated quantitative and fundamental analysis, as well as credit analysis of issuers, counterparties and guarantors. Further, the Board considered that Fidelity's investment professionals have sufficient access to global information and data so as to provide competitive investment results over time, and that those professionals also have access to sophisticated tools that permit them to assess portfolio construction and risk and performance attribution characteristics continuously, as well as to transmit new information and research conclusions rapidly around the world. Additionally, in its deliberations, the Board considered Fidelity's trading, risk management, compliance, cybersecurity, and technology and operations capabilities and resources, which are integral parts of the investment management process.

Shareholder and Administrative Services. The Board considered the nature, extent, quality, and cost of advisory, administrative, and shareholder services to be performed by the Investment Advisers and their affiliates under the Advisory Contracts and under separate agreements covering transfer agency, pricing and bookkeeping, and securities lending services for the fund. The Board also considered the nature and extent of the supervision of third party service providers, principally custodians, subcustodians, and pricing vendors.

The Board noted that the growth of fund assets over time across the complex allows Fidelity to reinvest in the development of services designed to enhance the value and convenience of the Fidelity funds as investment vehicles. These services include 24-hour access to account information and market information over the Internet and through telephone representatives, investor education materials and asset allocation tools. The Board also considered that it reviews customer service metrics such as telephone response times, continuity of services on the website and metrics addressing services at Fidelity Investor Centers.

Investment Performance. The fund is a new fund and therefore had no historical performance for the Board to review at the time it approved the fund's Advisory Contracts. The Board considered the Investment Advisers' strength in fundamental, research-driven security selection, which the Board is familiar with through its supervision of other Fidelity funds. The Board also considered the fact that it oversees funds managed by FMR that have similar investment objectives and policies as the fund.

Based on its review, the Board concluded that the nature, extent, and quality of services to be provided to the fund under the Advisory Contracts should benefit the shareholders of the fund.

Competitiveness of Management Fee and Total Expense Ratio. In reviewing the Advisory Contracts, the Board considered the fund's proposed management fee rate out of which FMR will pay all "fund-level" expenses, with certain limited exceptions, and the projected total expense ratio of the fund. The Board noted that the fund's proposed management fee rate is below the median fee rate of funds with similar Morningstar investment objective categories and comparable investment mandates, regardless of whether their management fee structures are comparable. The Board also considered that the projected total net expense ratio of the fund is below the median of those funds and classes used by the Board for management fee comparisons that have a similar sales load structure.

The Board also noted that FMR has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets exceed 0.60% through November 30, 2025.

Based on its review, the Board concluded that the fund's management fee and projected total expense ratio were reasonable in light of the services that the fund and its shareholders will receive and the other factors considered.

Costs of the Services and Profitability. The fund is a new fund and therefore no revenue, cost, or profitability data were available for the Board to review in respect of the fund at the time it approved the Advisory Contracts. In connection with its consideration of future renewals of the fund's Advisory Contracts, the Board will consider the revenues earned and the expenses incurred by Fidelity in conducting the business of developing, marketing, distributing, managing, administering and servicing the fund and servicing the fund's shareholders.

Economies of Scale. The Board will consider economies of scale when there is operating experience to permit assessment thereof. It noted that, notwithstanding the entrepreneurial risk associated with a new fund, the management fee was at a level normally associated with very high fund net assets, and Fidelity asserted to the Board that the level of the fee anticipated economies of scale at lower asset levels even before, if ever, economies of scale are achieved. The Board also noted that the fund and its shareholders would have access to the very considerable number and variety of services available through Fidelity and its affiliates.

Based on its evaluation of all of the conclusions noted above, and after considering all factors it believed relevant, the Board concluded that the advisory and sub-advisory fee arrangements are fair and reasonable, and that the fund's Advisory Contracts should be approved.

1.9912342.100

REF-SANN-0425

Item 8.

Changes in and Disagreements with Accountants for Open-End Management Investment Companies

See Item 7.

Item 9.

Proxy Disclosures for Open-End Management Investment Companies

See Item 7.

Item 10.

Remuneration Paid to Directors, Officers, and Others of Open-End Management Investment Companies

See Item 7.

Item 11.

Statement Regarding Basis for Approval of Investment Advisory Contract

See Item 7.

Item 12.

Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies

Not applicable.

Item 13.

Portfolio Managers of Closed-End Management Investment Companies

Not applicable.

Item 14.  

Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers

Not applicable.

Item 15.

Submission of Matters to a Vote of Security Holders

There were no material changes to the procedures by which shareholders may recommend nominees to the Fidelity Summer Street Trust’s Board of Trustees.

Item 16.

Controls and Procedures

(a)(i)  The President and Treasurer and the Chief Financial Officer have concluded that the Fidelity Summer Street Trust’s (the “Trust”) disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act) provide reasonable assurances that material information relating to the Trust is made known to them by the appropriate persons, based on their evaluation of these controls and procedures as of a date within 90 days of the filing date of this report.

(a)(ii) There was no change in the Trust’s internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act) that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the Trust’s internal control over financial reporting.

Item 17.

Disclosure of Securities Lending Activities for Closed-End Management Investment Companies

Not applicable.

Item 18.

Recovery of Erroneously Awarded Compensation

(a)

Not applicable.

(b)

Not applicable.

Item 19.

Exhibits

(a)	(1)	Not applicable.
(a)	(2)	Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.
(a)	(3)	Not applicable.
(b)		Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) is furnished and attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Fidelity Summer Street Trust

By:	/s/Stacie M. Smith
	Stacie M. Smith
	President and Treasurer (Principal Executive Officer)
Date:	March 25, 2025

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/Stacie M. Smith
	Stacie M. Smith
	President and Treasurer (Principal Executive Officer)
Date:	March 25, 2025

By:	/s/Stephanie Caron
	Stephanie Caron
	Chief Financial Officer (Principal Financial Officer)
Date:	March 25, 2025